Open-ended, world-building sandbox games are spawning at an increasingly rapid pace on iOS of late, with each offering a slightly different twist on Minecraft's addictive mix of exploration, scavenging, building, and crafting. While Terraria builds off of the Minecraft vibe in some interesting and adventurous ways, Junk Jack X copies it a bit too blatantly. Lack of originality aside, that's not entirely a bad thing. Translating many of the familiar-looking gameplay and visual elements to 2D works fairly well, offering moments of fun for patient players with collection obsessions.